CSS 2.1 Reference: outline-width Property

The outline-width property is used to specify the width of the outline. The outline property generates an outline around the content and border area of the element's box. See the Box Model for a description of the boxes that are generated for elements and the relative position of the content area and borders. Unlike the border property, the outline property is displayed on top of the element's box and it does not influence the size or position of the element's box.

This property is specified by using a length, or a keyword, according to the syntax shown above.

CSS Example: The outline-width properties are set using a length for the <h1> element and a keyword for the <h2> element.

h1 {outline-color: red;
    outline-style: solid;
    outline-width: 10px;
}
h2 {outline-color: red;
    outline-style: solid;
    outline-width: thick;
}

• thin
• medium
• thick
• inherit - The inherit keyword is used to specify that the value for this property should be taken from the parent element. If inherit is used with the root element, then the initial value for this property will be used.